The present invention relates to an apparatus for cleaning seafood, and more particularly to an assembly for a machine that is used to clean crustaceans, such as shrimp, prawns, crawfish, and the like.
Machines for peeling shrimp and prawns have been known since about the early 1950""s. One of such machines is disclosed in U.S. Pat. No. 2,537,355 issued on Jan. 9, 1951 to Fernand S. Lapeyre, et al. In that machine, a channel is created for receiving unpeeled shrimp and for slowly peeling the crustaceans, removing hulls, shells, appendages, and other inedible portion of the crustaceans. The apparatus of the ""355 patent uses a plurality of rollers, along which the seafood item slides, assisted by gravity and water flow. The shrimp are moved from one channel created by the rollers to another by reciprocating rotation of the rollers, causing the peeling of the shrimp and removal of the inedible portions. Pressure fingers hold the shrimp in firm contact with the rollers to facilitate peeling. The fingers are formed to approximately correspond to the contours of the channels formed between the rollers. The rollers move the shrimp from an elevated upstream portion of the roller assembly downstream, from where the peeled seafood item is deposited into a collector, while the inedible, peeled away portions of the shrimp are disposed of. The seafood cleaning machine of the ""355 patent was the industry standard for many years. An improvement to the ""355 patent is shown in U.S. Pat. No. 2,778,055 issued to Lapeyre, et al. in 1957 for xe2x80x9cMachine for Peeling Shrimp.xe2x80x9d In accordance with the ""055 patent, the roller assembly has a bottom roller, parallel side rollers disposed on opposite sides of the bottom roller and spaced above the bottom roller. The peeling channel is formed between the elevated rollers and the bottom rollers. Insert rollers are positioned between the bottom and side rollers to cover up crevices or spaces formed between the bottom roller and the elevated rollers. The inserts are strapped down in a resilient connection to the shrimp-peeling machine.
Another example of a shrimp peeling machine is shown in U.S. Pat. No. 2,781,544 issued in 1957 for xe2x80x9cSeafood Cleaning Machine.xe2x80x9d In that patent, oscillating rollers are mounted in contact with the top surface of a shrimp-receiving platform. The surfaces of the rollers and the platform have different coefficients of friction so that the shrimp which is received in a crotch between the rollers is caused to rotate until the loose ends of the shells are caught between the rollers and the platform, and the shell is unwound from the shrimp.
While these devices worked satisfactory, it has been observed that with time, shrimp shells and appendages tend to accumulate on the rollers and cause separation between the rollers. For instance, the insert rollers may be lifted from the crotch area between the larger diameter rollers, such that an unusually large crevice is created between the insert rollers and the larger diameter rollers. As a result of the debris accumulation, the peeled shrimp may get caught in the spaces between the rollers, which will cause pinching of an edible portion of the seafood item and damage to the edible portion of the product.
Additionally, the insert rollers, which are held down at both ends by hold down straps tend to form a curvature when too much debris accumulates on the insert rollers. The insert rollers then create a xe2x80x9cbowxe2x80x9d in the mid-section, separating themselves from a frictional contact with the larger diameter rollers. Water that is supplied to help move the shrimp and remove the debris, seeps into the created crevice and is lost. Further, since the rollers are oscillating, the peeled hulls are pushed down between the rollers, then pulled up again above the rollers, which interferes with the normal peeling of the shrimp.
It was also observed that with the machines where the narrow insert rollers have the same diameter from the upstream portion of the cleaning machine to the downstream portion thereof, hulls or whiskers of the crustacean may cling to the shrimp body, even when the shrimp reach the downstream portion of the machine. Consequently, some shrimp remain under-peeled. This effect is particularly pronounced in cases where the processed product has different sizes.
The present invention contemplates elimination of drawbacks associated with the prior art and provision of an improved assembly for a seafood cleaning machine.
It is, therefore, an object of the present invention to provide an assembly for a seafood cleaning machine that reduces the amount of damage of the edible portions of the cleaned items.
It is another object of the present invention to provide an assembly for a machine designed for cleaning shrimp that reduces the buildup of peeled inedible portions of the shrimp.
It is a further object of the present invention to provide an assembly for a seafood cleaning machine that increases efficiency and productivity of the cleaning machine, while minimizing loss of the product to over-peeling.
These and other objects of the present invention are achieved through a provision of an assembly for a seafood cleaning machine that comprises a plurality of power rollers positioned in a spaced-apart relationship to each other and are adapted for reciprocating partial rotation about their longitudinal axes. A plurality of secondary, smaller diameter, rollers are mounted between the power rollers in frictional contact with the adjacent power rollers. A plurality of insert rollers are fitted in the spaces between the power rollers and the secondary rollers to create pinching channels for the hull, appendages, whiskers and other inedible portions of crustaceans.
Each insert roller has an outside diameter that varies from the upstream portion of the assembly to the downstream portion thereof. A narrow section of each insert rollers is mounted adjacent the upstream portion, while the wider portion of the insert roller is positioned near the downstream portion. As a result, a tighter space is formed upstream between the rollers, which helps to engage smaller portions of the hull, or shrimp shell. When the smaller elements of the inedible portions are caught between the rollers, there is less probability that the rollers pinch edible meat and damage the seafood item.
The assembly of the present invention is also more efficient in cleaning away the debris of the peeled away portions and eliminating any build-up. This benefit is achieved through a provision of a double level of water spray directed to the insert rollers. One level of the water supply is provided above the insert rollers, sending intermittent sprays of water, followed by a flushing cycle, from one or more transverse upper conduits mounted above the rollers. The second level of the water spray is delivered from one or more transverse lower conduits equipped with a plurality of spray nozzles located below the insert rollers. A combination of two-level time-regulated water supply eliminates build-up of debris on the insert rollers and helps increase efficiency of the seafood cleaning operation.